With the rapid development of computer and electronic technologies, displays have been disposed on many portable electronic devices to show various forms of information, such as texts, pictures or video information. Some displays, such as LCD displays, use an LED array or a fluorescent lamp as a backlight module, and use a liquid crystal tunable filter to control the contrast of the light emitted from the backlight module to display graphics thereon. The luminous intensity of the light emitted from the backlight module, i.e. a backlight luminous intensity can be controlled by an operating system of the electronic device. Thus, the electronic device may control the brightness of the display by controlling the luminous intensity of the light, thereby meeting the requirements of different applications.
In conventional technologies, the system platform of many portable electronic devices may provide a specific application programming interface (API). Applications may use the API to set or adjust the backlight luminous intensity of the display. However, the backlight luminous intensity can only be reduced to a finite non-zero minimum value. Therefore, when the backlight luminous intensity is at the minimum value, the brightness of the display may still be maintained at a relatively low brightness level. Under many circumstances, especially when an environmental luminous intensity is extremely low, the relatively low brightness level of the display is still too high relative to the environment, which may cause discomfort to a user.
Therefore, there is a need of a method and apparatus for adjusting the brightness of a display, which is capable of providing a broader brightness configuration of the display, especially with a much lower limit of the brightness.